"I met Lynne a few years ago backstage with [my daughter] Ali at Britney's concert at the Meadowlands [Sports Complex in New Jersey], we just connected and we kept in touch," Zarin tells PEOPLE. "When Lynne comes to town we try to meet and catch up. She called me a couple of months ago and said she was coming to New York."

Zarin admits they may be an unexpected pair, but says they've bonded over motherhood.

"It is [surprising]," she says, "I mean I'm a Jewish girl from Long Island, and she's from Louisiana, so you couldn't get more apples and oranges. (Both have also authored books about motherhood.) "But we're both moms who love our kids and who would do anything to protect them. And Ally and Jamie Lynn are around the same age."

"We talked about Mother's Day, what we got, about New Orleans, about traveling," Zarin says of their dinner. "Her kids are doing fantastic. Her grandkids are her life. She looks amazing. She's in amazing shape; she works out. She was really happy."